Profits for the year are now likely to be between £50 million and £55m, up from previous estimates of between £40m and £45m.
However, the firm also warned that, despite the strong performance, uncertainty remains due to the pandemic. Bosses said future restrictions and colleague absences could play a part.
But the biggest concerns remain over supply issues in the new car market, with the industry struggling with a global shortage of certain semiconductor components which are used extensively in modern motors.
The lack of new vehicles is underpinning the used car market, with recent data showing sales of used vehicles hitting record highs.
Vertu, which has 155 sales outlets and is headed by chief executive Robert Forrester, told investors: “The group continues to experience strong used vehicle gross margin retention, driven by the exceptional UK used car market conditions.
“The group's like-for-like new vehicle order take for the key month of September is currently running in excess of prior year levels, however, there is a risk that well documented new vehicle supply shortages will result in vehicle deliveries being delayed into future periods.”
Following the upgrade, the firm is to reintroduce a dividend for shareholders.
Sanjay Vidyarthi, an analyst at Liberum, said: "August is typically one of the quietest months of the year, so to see this level of upgrade in such a short space of time points to remarkable market conditions, as well as strong trading by the company."